ARTICLES Chinese Science Bulletin 2003 Vol. 48 No.1 16— 23 choidea from the Yixian Formation. In the past two years a number of pterodactyloid A new pterosaur pterosaurs have been discovered from the Jiufotang For- mation, which represents the second horizon of the Jehol (Pterodactyloidea, Group preserving pterosaurs. In this paper we will report a complete skeleton of a new pterodactyloid pterosaur from Tapejaridae) from the Early the Jiufotang Formation in Dongdadao of Chaoyang, Cretaceous Jiufotang western Liaoning Province. The fossil is referred to the family Tapejaridae. Members of the Tapejaridae have pre- Formation of western viously been known only in the late Early Cretaceous Santana Formation (Aptian/Albian) of Brazil[14,15]. Sinop- Liaoning, China and its terus represents the earliest record of this family. Two pterosaur assemblages appear to be present in implications for the Jehol Group, represented by taxa from the lower * Yixian Formation and the upper Jiufotang Formation, biostratigraphy respectively. These two pterosaur assemblages are more or less comparable to those of the Solnhofen and the Santana WANG Xiaolin & ZHOU Zhonghe pterosaur assemblages. The age of the Jehol pterosaur Institute of Vertebrate Paleontology and Paleoanthropology, Chinese assemblages is between the Solnhofen lithographic lime- Academy of Sciences, Beijing 100044, China stone (Tithonian) and the Santana Formation (Ap- Correspondence should be addressed to Wang Xiaolin (e-mail: xlinwang tian/Albian). @263.net) 1 Systematic paleontology Abstract In this article we describe a new and excep- tionally well-preserved pterodactyloid pterosaur, Sinopterus Order Pterosauria Kaup, 1834 dongi gen. et sp. nov. from the Jiufotang Formation in west- Suborder Pterodactyloidea Plieninger, 1901 ern Liaoning Province of northeast China. The new species is Family Tapejaridae Kellner, 1989 referred to the family Tapejaridae, representing its first re- Genus Sinopterus gen. nov. cord outside Brazil. It also represents the earliest occurrence Sinopterus dongi gen. et sp. nov. as well as the most complete skeleton of the family. Some (Figs. 1 and 2; Tables 1 and 2) revisions are made about the family according to the mor- phological observations of the postcranial bones of Sinop- Diagnosis. Medium-small sized pterodactyloid. terus. Two pterosaur assemblages appear to have existed in Wingspan about 1.2 m. Skull length about 170 mm. Ros- the Jehol Group, represented by the lower Yixian Formation trum slender and pointed, edentulous, with a horny beak. and upper Jiufotang Formation, respectively. The lower Skull long and low. Sagittal crest of premaxilla and den- pterosaur assemblage shows some resemblance to that of the tary low and small. Posterior crest of the premaxilla Late Jurassic in Solnhofen (Tithonian) by sharing members curved upward, separate from the skull, and parallel to the of the Pterodactylidae and Anurognathidae. The upper one parietal crest. Nasopreorbital fenestra large and long shows more resemblance to that of the Early Cretaceous (length about 2.5 times the height), exceeding one-third Santana Formation (Aptian/Albian) by comprising only the total length of the skull. Radius, wing metacarpal and pterodactyloids such as the Tapejaridae. The age of the Yixian Formation is younger than that of the Solnhofen first phalanx of the wing digit about 1.5, 1.6 and 2 times lithographic limestone, and the age of the Jiufotang Forma- the length of the humerus, respectively. Carpals large and tion (Aptian) is slightly older than the Santana Formation. unfused. Scapula strongly curved. Coracoid expanded at the articulation to the scapula. Tibia about 1.4 times the Keywords: Pterodactyloidea, Tapejaridae, Sinopterus, Jiufotang Formation, Jehol Group, biostratigraphy, Chaoyang, Liaoning. length of the femur. Metatarsals Ⅰ through Ⅳ progres- sively shorter. Metatarsal Ⅲ about 22.1% the length of The Early Cretaceous Jehol Group, which comprises the wing metacarpal, and metatarsal Ⅴ is less than 1/5 the Yixian and Jiufotang formations, has yielded not only the length of metatarsal Ⅰ. [1— 3] exceptionally well-preserved early birds , feathered Holotype. A nearly completely articulated skeleton. dinosaurs[4,5], mammals[6,7] and angiosperms[8,9] but also Institute of Vertebrate Paleontology and Paleoanthropol- many beautifully preserved pterosaurs such as Eosip- ogy (IVPP) V13363. terus[10] and Haopterus[11] of Pterodactyloidea, and Den- Locality and horizon. Lamagou, Dongdadao, drorhynchoides[12] and Jeholopterus[13] of Rhamphorhyn- Chaoyang, Liaoning Province; Jiufotang Formation, late * The Chinese version of this was published on Chinese Science Bulletin, 2002, 47(20): 1521, which should be referred for citation of the naming of the genus and species. 16 Chinese Science Bulletin Vol. 48 No. 1 January 2003 ARTICLES Fig. 1. Line drawing of Sinopterus dongi gen. et sp. nov. holotype (IVPP V 13363). CA: Carpal; CR: coracoid; CV: cervical ver- tebra; D: dentary; FE: femur; FI: fibula; H: humerus; J: jugal; M: maxilla; MC Ⅰ— Ⅲ: metacarpals Ⅰ— Ⅲ; MD Ⅰ— Ⅲ: man- ual digits Ⅰ— Ⅲ; N: nasal; PC: parietal crest; PM: premaxilla; PMC: premaxillary sagittal crest; PT: pteroid; R: radius; SC: scapula; ST: sternum; TI: tibia; U: ulna; WD 1— 4: first through fourth phalanges of the wing digit; WMC: wing metacarpal; Ⅰ— Ⅴ: metatarsals Ⅰ— Ⅴ; 1— 5: pedal digits Ⅰ— Ⅴ. Table 1 Measurements (length) of the skull of Sinopterus dongi gen. et wing; species name is dedicated to Chinese dinosaurolo- sp. nov. (IVPP V 13363) (mm) gist Dong Zhiming. Skull (tip of premaxilla to end of the parietal crest) 170 Skull and mandible. The skull is laterally pre- Tip of premaxilla to squamosal 146 served and edentulous. The premaxilla is fused with the Anterior margin of nasopreorbital fenestra to squamosal 101 maxilla anteriorly. The anterior premaxilla is long and Tip of premaxilla to anterior margin of nasopreorbital fenestra 48 pointed, with a horny beak. Both the premaxilla and the Skull height (at the quadrate) 30 parietal have a narrow crest. The premaxillary sagittal Skull height (at the highest point of premaxilla) 32 crest is anteriorly low and flat; it extends horizontally Parietal crest 35 Nasopreorbital fenestra 61 backwards until the posterior margin of the skull. The Nasopreorbital fenestra height 25 parietal crest is isolated from that of the premaxilla. The Diameter of the orbit 15a) crest of the premaxilla starts to be separated from the rest Horny beak 13a) of the skull from the middle of the nasopreorbital fenestra; Dentary 125 it is relatively thick ventrally and thin dorsally, similar to [14,16] Dentary height (at the highest point of the dentary crest) 14 that of Tapejara wellnhoferi ; bony sheath and its im- a) Approximate or estimated value. pression are observable near the outer margin of the crest for the protection of the crest as suggested earlier[16]. The Early Cretaceous (Aptian). maxilla has a straight ventral margin, and forms an obtuse Etymology. Sinae (Latin), China; pterus (Greek), angle with the ventral margin of the premaxilla, which is Chinese Science Bulletin Vol. 48 No. 1 January 2003 17 ARTICLES Fig. 2. Holotype Sinopterus dongi gen. et sp. nov. (IVPP V 13363). 1, Skeleton; 2. skull. 18 Chinese Science Bulletin Vol. 48 No. 1 January 2003 ARTICLES Table 2 Length (mm) of postcranial bones of Sinopterus dongi gen. et mily[14— 17]. sp. nov. (IVPP V 13363) The nasal is long and unfused with the premaxilla Left Right and jugal; it has a needle-shaped ventral process. The Scapula 40 39a) nasal extends towards the premaxilla anteriorly for about Coracoid 35 36 one-third the length of the nasopreorbital fenestra. Humerus 59 58 The frontal and parietal are fused, without obvious Ulna 88 87.5 suture. The frontal is an inverse triangle-shaped. The pa- Radius 84 85 b) rietal has a posteriorly lifted crest; the crest is better de- Pteroid 29 38 [14,16] Wing metacarpal 77b) 95 veloped than in T. wellnhoferi , and it is also more Metacarpals Ⅰ— Ⅲ - 93a) curved upwards. The ascending process of the jugal con- First phalanx of manual digit Ⅰ - 12.5 tacts the nasal. The anterior process of the jugal is long Second phalanx of manual digit Ⅰ - 8a) and slender; it lies near the ventral margin of the nasopre- First phalanx of manual digit Ⅱ - 7.5 orbital fenestra, and is about two-thirds the length of the Second phalanx of manual digit Ⅱ - 12.5 nasopreorbital fenestra. Third phalanx of manual digit Ⅱ - 10 The lower jaw is completely preserved and edentu- First phalanx of manual digit Ⅲ - 12.5 lous; it is robust; its ventral sagittal crest is straight poste- Second phalanx of manual digit Ⅲ - 3 riorly but pointed anteriorly. Bones of the lower jaw ap- Third phalanx of manual digit Ⅲ - 12 pear to be well fused. Fourth phalanx of manual digit Ⅲ - 4b) Compared to other members of the Tapejaridae, the First phalanx of wing digit 105.5b) 121 skull of Sinopterus is low and long, the skull length (from Second phalanx of wing digit 91 88 the tip of the premaxilla to the posterior margin of the Third phalanx of wing digit 65.5 63 parietal crest) is about 170 mm, which is about 5 times its Fourth phalanx of wing digit 33 32 height (excluding the height of the lower jaw). The naso- Femur 74a) 74 preorbital fenestra is large and more than one-third the Tibia 104 104 length of the skull. Fibula 20 20 Vertebral column. There are 7 cervical vertebrae Metatarsal Ⅰ 25 24.5 preserved in articulation; they are long and robust. The Metatarsal Ⅱ 23 23.3 length of the third through seventh cervicals are 15.5 mm, Metatarsal Ⅲ 20.5 21a) 19.5 mm, 20.5 mm, 21 mm and 19 mm, respectively. The Metatarsal Ⅳ 19 19 neck is over 100 mm long. The dorsal vertebrae are disar- Metatarsal Ⅴ - 4.5 ticulated in preservation. The estimated number of the First phalanx of pedal digit Ⅰ 2 b) 10.5 dorsals is 11— 12; the centrum is often isolated from the Second phalanx of pedal digit Ⅰ - 6 neural spine; it is about 5— 7 mm long and procoelous.